What Is Gene Drive?

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What Is Gene Drive? The Science: What is gene drive? What is gene drive? Gene drive is a genetic phenomenon that occurs in nature and causes a selected trait to spread rapidly through a species via sexual reproduction over several generations. Gene drive works by increasing the likelihood that a modified gene will be inherited by its offspring. Normally, genes have a 50/50 chance of being inherited, but gene drive How is Target Malaria using systems could increase that chance to upwards gene drive technology? of 99 percent. This means that over the course of several generations, a selected trait could become We aim to tackle malaria at the source. Target increasingly common within a specific species. Malaria is using gene drive approaches to insert a modification in malaria mosquitoes that would Researchers have been studying how to harness affect the mosquito’s ability to reproduce. By gene drives to solve some of society’s most reducing the population of malaria mosquitoes, intractable problems for a long time. Public health we aim to reduce the transmission of the disease. and ecosystem conservation are two of the main areas where research has focused, although other Worldwide there are more than 3,500 species of uses are also possible. mosquito, with 837 of them in Africa. Of these, a single cluster of three very closely related What are gene drive applications species are responsible for most of the malaria transmission – Anopheles gambiae, Anopheles in public health? coluzzii and Anopheles arabiensis. In public health, several proposals have been The project is investigating the use of genes that made which would use gene drive to limit the produce enzymes (called nucleases) that cut spread of diseases, particularly those spread specific sequences of DNA. The concept for these by insect vectors, such as malaria, which affect nucleases is based on Homing Endonuclease several hundred million people a year. For Genes (HEGs) which are a class of nuclease genes, malaria, this could be done by inserting a trait found in simple single celled organisms, which which makes the mosquitoes unable to host are capable of copying themselves from one the malaria parasite, or one which affects the chromosome to another. local population dynamics of the mosquitoes to reduce their numbers. Two of the main areas we are currently Gene drive approaches to vector control focusing on are biasing the sex ratio represent a potentially highly effective, long term of mosquito populations and reducing and cost-effective tool that could, in the context female fertility. of integrated approaches, help eliminate malaria. july 2020 targetmalaria.org | [email protected] page 1 of 2 When introduced in the malaria mosquito, the What is the timeline for gene drive nuclease work by identifying and cutting through essential genes targeted by our researchers, such applications for malaria control? as fertility genes. The interrupted gene will no longer function, and modified mosquitoes will be Current research on gene drive is at an early affected according to the nature and importance stage, and so definitive decisions about gene of the gene. drive-based products is premature at best. Based on current progress, products ready for The ultimate goal is to produce modified field testing are 5 years out, possibly longer. malaria mosquitoes that can pass these genes This gives scientists and stakeholders, on to a disproportionately high percentage of particularly those from countries where gene their offspring, so the modification is spread drives might one day be employed, time to throughout the specific population relatively consider the important questions of regulation, quickly and is effectively “self-sustaining”. risk assessment, ethics, and engagement, and to This makes the reduction of the malaria prepare for assessing an actual application. mosquito vector population relatively cost effective and simple to implement because the mosquitoes themselves do the work. Gene drives increase gene spread For more information go to our website: www.targetmalaria.org/ourwork july 2020 targetmalaria.org | [email protected] page 2 of 2 .
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  • Gene Drives for Malaria Control and Elimination in Africa
    GENE DRIVES FOR MALARIA CONTROL AND ELIMINATION IN AFRICA HIGH LEVEL APET REPORT • GENE DRIVES FOR MALARIA CONTROL AND ELIMINATION IN AFRICA About the AU and NEPAD The African Union (AU) The African Union (AU) is a continental union consisting of all 55 countries on the African continent. It was established on 26 May 2001 in Addis Ababa, Ethiopia, and launched on 9 July 2002 in South Africa, with the aim of replacing the Organisation of African Unity (OAU). The most important decisions of the AU are made by the Assembly of the African Union, a semi-annual meeting of the heads of state and government of its member states. The AU’s secretariat, the African Union Commission, is based in Addis Ababa. The AU was established following the 9th September 1999 Sirte Declaration of the Heads of State and Governments of the Organisation of the African Unity (OAU). The AU is based on a common vision of a united and strong Africa and on the need to build a partnership between governments and all segments of civil society, in particular, women, the youth and the private sector, in order to strengthen solidarity and cohesion amongst the peoples of Africa. As a continental organization, it focuses on the promotion of peace, security and stability. The development work of the AU is guided by the AU Agenda 2063, which is a 50-year plan to harness Africa’s comparative advantage to deliver on the vision of “The Africa We Want”. The New Partnership for Africa’s Development (NEPAD) Created by the African Union, the New Partnership for Africa’s Development (NEPAD) is a strategic framework for Pan-African socio- economic development.
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  • A CRISPR Endonuclease Gene Drive Reveals Two Distinct Mechanisms of Inheritance Bias
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  • Resistance to Gene Drive
    Resistance to gene drive Many existing methods of malaria control are facing difficulties in maintaining effective performance, from insecticide and drug resistance to increasing costs of interventions. Controlling the malaria vector, the mosquito, remains the frontline for disease elimination. Target Malaria aims to develop new genetic technologies in a strategy known as gene drive to reduce the malaria mosquito population and thus reduce malaria transmission. This means that both the CRISPR/Cas transgene and female infertility spread through mosquito Gene drive involves a genetic mechanism population at far greater rates than would occur designed to spread through a population by normal inheritance mechanisms, ultimately while at the same time reducing the leading to reductions in the overall numbers of mosquito population and decreasing malaria vectors. malaria transmission. Gene drive is an especially appealing strategy as it could be deployed in remote locations, can Resistance potential work in parallel with the health care system while not being dependent on it, Just as antibiotic use to treat bacterial infection is potentially cost effective, can be used can lead to drug-resistant bacteria, any method in complementarity with other vector of mosquito population control - such as the control methods and has the potential for use of insecticides - can lead to mosquitoes that long term and sustainable impact. are resistant to that method. Likewise, the risk exists that some form of resistance to the gene drive could emerge. Resistance arises through a The Target Malaria gene drive approach exploits common cause of natural selection, whatever the a transgene encoding the nuclease CRISPR/ resistance is against.
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  • How Can We Use Genetic Engineering to Get Rid of Malaria for Good?
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  • STOA Workshop the Science and Ethics of Gene Drive Technology
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  • Viral Gene Drive in Herpesviruses ✉ ✉ Marius Walter 1 & Eric Verdin 1
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  • Targeting Evolutionary Conserved Sequences Circumvents the Evolution of Resistance in a Viral Gene Drive Against Human Cytomegalovirus
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  • Advanced Gene Editing: CRISPR-Cas9
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  • Potential and Risks of Recent Developments in Biotechnology
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